When a dilapidated cargo ship sinks, killing the illegal immigrants packed in below decks, the man responsible goes free, but not for long. Two weeks later, he is found dead with a knife in his back. Human trafficker Thomas Blackburn lived and died in the heart of London's West Indian community and, when the attitude of the local murder squad Chief Superintendent is deemed likely to aggravate race relations, George Gently is called in to oversee the case.